This is a proposal for help to defray the cost of the 2005 International Molecular Biology of Hepatitis B Virus meetings, scheduled for Sept. 18th through the 21st, 2005. This is the next meeting in a series that has been held continuously since 1985. These are the definitive annual meetings in this field, which bring basic scientists in the field of HBV and hepatitis delta virus (HDV) together. HBV continues to be a major global and US public health problem. Despite a prophylactic vaccine, parenteral injections are needed and there is a vaccine failure rate of 5 - 10%. Moreover, for the more than 350 million people chronically infected with HBV (more than 15 million of whom are co-infected with HDV), the vaccine, is of no therapeutic value. It is thus critical that research continue and dialogue be nurtured between those working in the field. This is the annual meeting at which this dialogue occurs. With this in mind, and an eye on enabling the participation of junior investigators, support for the travel and participation of junior scientists is requested. Limited support for web site development is also needed. This year, the meeting is also strongly supported by the Hepatitis B Foundation, and thus, costs of the meeting are being minimized by using university and non profit staff and facilities in the US and Germany. The meeting will emphasize stimulating interaction and dialogue, through the 11 formal scientific sessions that always budget time for discussion, as well as less structured "networking" sessions. A theme for the 2005 meeting will be the liver immuno-cell-biology of disease and integration of tools useful in other fields to HBV and HDV. This will be facilitated by the keynote addresses and a special workshop.